IOL insertion apparatus and methods for making and using same

ABSTRACT

Apparatus, and methods of making and using apparatus, for inserting intraocular lenses (IOLs) are disclosed. The apparatus includes a hollow tube having an interior wall defining a hollow space through which an intraocular lens may be passed from the open space into an eye. A lubricity enhancing component is covalently bonded to the hollow tube at the interior wall in an amount effective to facilitate the passage of the intraocular lens through the hollow space. The lubricity enhancing component includes a substituent component effective to reduce hydrolysis of said lubricity enhancing component relative to an identical lubricity enhancing component without the substituent component.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to apparatus for inserting anintraocular lens through a small incision into an eye, to methods formaking such apparatus and to methods for inserting an intraocular lensinto an eye. More particularly, the present apparatus has enhancedlubricity and stability, can be relatively easily and effectivelymanufactured, and is useful for inserting a foldable intraocular lensinto an eye.

[0002] An intraocular lens (IOL) is implanted in the eye, for example,as a replacement for the natural crystalline lens after cataract surgeryor to alter the optical properties of (provide vision correction to) aneye in which the natural lens remains. IOLs often include an optic, andpreferably at least one flexible fixation member or haptic which extendsfrom the optic and becomes affixed in the eye to secure the lens inposition. The optic normally includes an optically clear lens.Implantation of such IOLs into the eye involves making an incision inthe eye. It is advantageous, to reduce trauma and speed healing, to havean incision size as small as possible.

[0003] IOLs are known which are foldable (deformable) so that the IOLcan be inserted through a smaller incision into the eye. A substantialnumber of instruments have been proposed to aid in inserting such afoldable lens in the eye.

[0004] Many of the prior art IOL insertion systems load and/or fold thelens at the distal end, that is, at the end inserted into, or closestto, the eye. Such “distal loading” systems often disadvantageouslyinclude a space consuming loading component at or near the distal end ofthe system which causes the distal end to be relatively large. Thisrelatively large distal end makes inserting the IOL through a smallincision more difficult, if not impossible. Systems which fold and loadthe IOL proximally of the distal end provide certain advantages, such asreduced stress on the IOL and/or inserter, relative to “distal loading”systems.

[0005] However, whether using a distal loading or proximal loadingsystem, one factor which has historically determined the minimumdiameter of the inserter tube involves the inserter tube itself. Forexample, the material from which the inserter tube is made, such aspolypropylene and the like polymeric materials, may have a relativelyhigh coefficient of friction, causing it to provide a relatively highamount of resistance to an optic made, for instance, from siliconepolymeric materials, as it passes through the tube. The amount ofresistance, and thus the amount of force (torque) required to pass anIOL through the tube, increases as the diameter of the tube decreases.Since increased torque on the IOL increases the potential for damage tothe IOL and/or the inserter tube, as well as injury to the patient, itis desirable to keep the required torque as low as possible.

[0006] One way to reduce the amount of force needed to pass an IOLthrough a small diameter insertion tube is to provide a lubricityenhancing component, such as a coating, on the exposed interior surfacesof the inserter. Examples of IOL inserters having an interior wallcoated or otherwise provided with a lubricity enhancing componentinclude Makker et al. U.S. Pat. No. 5,716,364 and Yang et al. U.S. Pat.No. 5,803,925. The disclosures of each of these patents are incorporatedin their entireties herein by reference.

[0007] The aforementioned Makker patent discloses a method of making aninserter that comprises compounding a hydrophilic lubricity enhancingcomponent such as glycerol monostearate (GMS) into the polypropyleneresin used to fabricate the inserter. The interior wall is preferablythen exposed to plasma and subsequently subjected to elevatedtemperatures for a sufficiently long time to cause the lubricityenhancing component to Abloom@ to the surface of the cartridge. Afterblooming, the lubricity enhancing component functions as a low-frictioncoating that is non-covalently bonded to the interior wall of theinserter.

[0008] The Yang et al. patent discloses an inserter having a lubricityenhancing component covalently bonded to an interior wall. An exemplarylubricity enhancing component disclosed in Yang et al. comprises acompound having the formula A-PEG, where A is a reactive group capableof covalently bonding to the surfaces of a polypropylene IOL inserter,and PEG is a residue of polyethylene glycol.

[0009] While many of the prior art lubricity enhancing components aregenerally satisfactory, further improvements are desirable. Forinstance, in inserters having non-covalently bonded GMS-based lubricityenhancing components such as those disclosed in the aforementionedMakker et al. patent, the blooming process may continue even afterexposure of the inserter interior wall to high temperatures has stopped,which can eventually result in excessive amounts of GMS on the surfaceof interior wall. Such inserters have the potential of causing excessGMS to be transferred onto the surface of an IOL optic during insertion,causing unsightly blemishes or streaks on the optic. The shelf life ofthese prior art GMS-based cartridges is limited to one year, forexample, to avoid this potential risk. On the other hand, prior artcartridges having covalently bonded lubricity enhancing components mayinvolve more complex manufacturing processes, require higher torque topass the IOL through the tube, or may be the potential risk of reducedstability, for example, because of hydrolysis of the coating, over time.Such prior art cartridges also have limited shelf life to avoid thispotential stability risk. Likewise, a simplified mode of generating anappropriate matrix for cross-linking of involved subsistent for examplea dialdehyde and a polymeric amine prior to dispersal and/or avoidanceof extended times associated with plasma treatment serves to enhanceindustrial efficiency and is progress in science as a useful art.

[0010] Accordingly, it would be advantageous to provide stable,long-lasting lubricity-enhancing coatings for IOL insertion apparatuswhich facilitate the passage of folded IOLs through the apparatus in acontrolled manner without using excessive force. It would also beadvantageous to devise cost-effective and simple methods of making andusing insertion apparatus.

SUMMARY OF THE INVENTION

[0011] New apparatus for injecting IOLs and methods for making and usingsuch apparatus have been discovered. The present apparatus achieveenhanced lubricity, thus providing for controlled insertion of an IOLinto an eye, for example, for the use of effective, reliable andnon-excessive amounts of force to inject a folded IOL into an eye. Thepresent system provides for controlled, reliable, easy and convenientinsertion of IOLs, including those made of materials which wouldordinarily exert relatively high frictional forces against the interiorwall of the inserter. In addition, the present invention provides forinserting folded IOLs through very small incisions in the eye. Thepresent IOL insertion methods are straightforward, easy to practice, andinvolve little or no modification of surgical techniques. The methodsfor making the insertion apparatus are also straightforward and easy topractice.

[0012] In general, the present invention involves apparatus forinserting IOLs into an eye which include an improved lubricity enhancingcomponent covalently bonded to the apparatus, for example, at theinterior hollow wall defining a hollow space through which an IOL ispassed, to at least assist in facilitating the passage of the IOLsthrough the apparatus. Covalent attachment or bonding of such lubricityenhancing components is particularly effective since the amount of suchcomponent present and therefore, at least to some extent, the degree ofenhanced lubricity, is conveniently controlled and stable on a long termbasis, for example has a long term shelf life. In addition, there isreduced chance or risk of the lubricity enhancing component beingdisadvantageously removed from the surface of the apparatus as the IOLpasses through the apparatus into the eye.

[0013] The use of the present covalently bonded lubricity enhancingcomponents allows successful injection of foldable IOLs, such assilicone-based IOLs, foldable acrylic-based IOLS and the like, includingthose which would ordinarily exert relatively large frictional forcesagainst the interior wall of the inserter, employing inserters made, forinstance, of polypropylene and the like polymeric materials, throughincisions about 3.5 mm or less, preferably about 3.0 mm or about 2.8 mmor less, and still more preferably less than 2.8 mm. Furthermore,relatively little force is required to perform the injection.

[0014] In one broad aspect of the invention, apparatus for inserting anintraocular lens through a small incision into an eye are provided. Suchapparatus comprise a hollow tube including an interior wall defining ahollow space through which an intraocular lens may be passed from thehollow space into the eye. An improved lubricity enhancing component iscovalently bonded to the hollow tube at the interior wall in an amounteffective to facilitate the passage of the intraocular lens through thehollow space. The lubricity enhancing component includes a substituentcomponent effective to increase the stability, for example, the chemicalstability, preferably to reduce hydrolysis, of the lubricity enhancingcomponent relative to an identical lubricity enhancing component withoutthe substituent component.

[0015] In a particularly useful embodiment, the substituent component ofthe lubricity enhancing component is selected from non-hydroxy groups,that is, the substituent component is other than hydroxy, and iseffective to reduce hydrolysis of the lubricity enhancing componentrelative to an identical lubricity enhancing component including one ormore hydroxy groups in place of the substituent component.

[0016] In one embodiment of the invention, the substituent component isselected from the class consisting of hydrocarbyl groups, substitutedhydrocarbyl groups and mixtures thereof. Preferably, the substituentcomponent has 1 to about 4 carbon atoms per group. As used herein, theterm Ahydrocarbyl groups@ means groups made up of carbon and hydrogen,such as alkyl, alkenyl and the like. Substituted hydrocarbyl groups aregroups including carbon and hydrogen atoms and one or more other heteroatoms, such as one or more oxygen, nitrogen, phosphorous, sulfur and thelike atoms, and mixtures thereof.

[0017] In an advantageous embodiment of the invention, the substituentcomponent is selected from the class consisting of alkoxy groups having1 to about 4 carbon atoms and mixtures thereof.

[0018] In a very useful embodiment, the substituent component isselected from one or more methoxy groups.

[0019] In yet another embodiment, the lubricity enhancing component isderived from a precursor component including the substituent component,an alkylene oxide component, for example in the form of a polyalkyleneglycol component and the like, and an additional substituent componenteffective to covalently bond with at least one of the precursorcomponent and the hollow tube. The precursor component includes at leastone reactive substituent component effective to covalently bond to thehollow tube, for example, to the polymeric material of the hollow tube.In a particularly useful embodiment, the alkylene oxide component is anethylene oxide component, for example a polyethylene glycol component.The additional substituent component advantageously is an ethylenicallyunsaturated group. Preferably, the additional substituent component isselected from the class consisting of vinyl groups, acrylic groups,methacrylic groups and mixtures thereof. In a more preferred embodiment,the precursor component is methoxy polyethylene glycol monomethacrylate(mPEGMA). Advantageously, the precursor component includes mPEGMA of twoor more, preferably three, different molecular weights.

[0020] The hollow tube is preferably made of a polymeric material, morepreferably selected from polypropylene and the like materials. Inaddition, the hollow tube is preferably sized to pass the intraocularlens into the eye through an incision no larger than 3.5 mm. Morepreferably, the tube is sized to pass the intraocular lens into the eyethrough an incision no larger than 3.0 mm. More preferably still, thetube is sized to pass the intraocular lens into the eye through anincision no larger than 2.8 mm.

[0021] The apparatus of the present invention also preferably includes aloading portion sized and adapted to receive an IOL for passage into thehollow space of the tube. The loading portion is preferably sized andadapted to receive the IOL in an unfolded state, and to hold the IOL ina folded state. The loading portion can be structured to at leastfacilitate the folding of the IOL from the unfolded state to a foldedstate. The hollow space of the tube is preferably sized to receive theIOL in a folded state from the loading portion and to pass the foldedIOL to an open outlet through which the IOL is passed into an eye.Preferably, the lubricity enhancing component is provided on both thehollow tube and the loading portion of the apparatus.

[0022] Methods for inserting an IOL into an eye are included within thescope of the present invention. In one embodiment, such methods compriseplacing an outlet of a hollow tube in or near an incision in an eye, andpassing the intraocular lens from the hollow tube through the outletinto the eye. The hollow tube includes an interior wall defining ahollow space containing an IOL, preferably in a folded state. Animproved lubricity enhancing component is provided and is covalentlybonded to the hollow tube at or near the interior wall. The lubricityenhancing component includes a substituent component effective toenhance the stability, for example, the chemical stability, preferablyto reduce hydrolysis of, the lubricity enhancing component relative toan identical lubricity enhancing component without the substituentcomponent. Useful substituent components are disclosed elsewhere herein.

[0023] Methods of making an intraocular lens inserter apparatus areprovided and included within the scope of the present invention. In oneembodiment, such methods comprise contacting the interior wall of ahollow polymeric tube with a precursor material of an improved lubricityenhancing component and causing the precursor material to form thelubricity enhancing component covalently bonded to the polymericmaterial of the tube. The lubricity enhancing component includes atleast one substituent group effective to increase the stability, forexample the chemical stability, preferably to reduce hydrolysis, of thelubricity enhancing component relative to an identical lubricityenhancing component without the substituent component.

[0024] In one useful embodiment, the method includes a step of primingor pre-treating the interior wall, for instance by exposing the interiorwall to plasma for a sufficient amount of time to enhance covalentbonding between the lubricity enhancing agent and the polymeric materialof the tube, for example, so that the exposed surface of the wall is, orbecomes, more susceptible to being wetted by the solution of theprecursor material.

[0025] In an especially useful embodiment, the precursor materialincludes radical initiators, for instance UV and/or thermal radicalinitiators. The step of causing the precursor material to form acovalently bonded lubricity enhancing component preferably includesexposing the coating on the interior wall, for example the wettedinterior wall, to conditions suitable for activating the initiator orinitiators to form a covalently bonded coating on the interior surfaceof the tube. Advantageously, the precursor material includes both UV andthermal radical initiators, and the step of exposing the precursormaterial to conditions suitable for activating the initiators includes afirst stage of exposing the coating on the wall to ultraviolet light tocovalently bond the coating to the wall, and a second stage of exposingthe covalently bonded coating to elevated temperatures for a timesufficient to enhance the stability of the covalently bonded coating.

[0026] Each and every feature described herein, and each and everycombination of two or more of such features, is included within thescope of the present invention provided that the features included insuch a combination are not mutually inconsistent.

[0027] These and other aspects of the present invention will becomeapparent in the following detailed description and claims, particularlywhen considered in conjunction with the accompanying drawings in whichlike parts bear like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028]FIG. 1 is a schematic illustration showing an IOL inserter inaccordance with the present invention including a covalently bondedlubricity enhancing component thereon.

[0029]FIG. 2 is a fragmentary illustration of a small part of the IOLinserter shown in FIG. 1.

[0030]FIG. 3 is a front side view, in perspective, of an IOL inserter inaccordance with the present invention, with the load chamber in the openposition.

[0031]FIG. 4 is a side view, in perspective, of an IOL inserter inaccordance with the present invention, with the load chamber in theclosed position.

[0032]FIG. 5 is a front side view, in perspective, of the IOL insertershown in FIG. 4 loaded into a hand piece.

[0033]FIG. 6 is a side view, partly in cross-section, taken generallyalong line 6-6 of FIG. 5.

[0034]FIG. 7 is a somewhat schematic illustration showing the IOLinserter shown in FIG. 5, with the hand piece partially incross-section, being used to insert an IOL into an eye.

DETAILED DESCRIPTION OF THE DRAWINGS

[0035]FIG. 1 illustrates an IOL inserter, shown generally at 10,including a load chamber 12 and an injection tube 14. In FIG. 1, the IOLinserter 10, which is made of polypropylene, is shown after treatmentwith a lubricity enhancing precursor material. Preferably, the precursormaterial is selectively applied so that only the interior surfaces ofthe IOL inserter 10 are coated. This selective application may beachieved in any suitable manner such as by brushing with a microbrush,or by spraying, irrigating, or the like. Less desirably, the entireinserter 10 may be immersed in a bath of the precursor material so thatboth interior and exterior surfaces are coated.

[0036] The purpose of treating IOL inserter 10 with the precursormaterial is to coat all of the tubular interior surfaces of IOL inserter10 with a hydrophilic component, or coating, 20, as shown in FIG. 2.Coating 20 is covalently bonded to the inserter 10, that is, to thepolypropylene. Coating 20, which enhances the lubricity of IOL inserter10, for example of the lumens defined by load chamber 12 and injectiontube 14, as shown in FIG. 3, relative to the lubricity of an identicalIOL inserter without the covalently bonded coating 20. Such enhancedlubricity is effective to at least assist in facilitating the passage ofan IOL through the lumens of IOL inserter 10 into an eye.

[0037] The precursor material of the lubricity enhancing component,preferably a hydrophilic material, contains reactive groups orsubstituents that allow at least limited covalent attachment to thepolypropylene cartridge.

[0038] Importantly, the precursor material and the final coating 20include substituent groups effective to enhance the stability, forexample the storage stability or shelf life, of the IOL inserter 10relative to an identical IOL inserter including a lubricity enhancingcomponent without the substituent groups. Preferably, the substituentgroups are effective to reduce hydrolysis of the lubricity enhancingcoating relative to an identical lubricity enhancing coating orcomponent without the substituent groups.

[0039] Advantageously, the substituent groups are not —OH groups, thatis, are non-hydroxy groups. For instance, and without limitation, thesubstituent component may be selected from the class consisting ofhydrocarbyl groups, substituted hydrocarbyl groups, and mixturesthereof, preferably such groups having 1 to about 4 carbon atoms pergroup. In a very useful embodiment, the substituent component isselected from alkoxy groups, preferably alkoxy groups having 1 to about4 carbon atoms per group, and mixtures thereof. A particularly usefulsubstituent component is one or more methoxy groups.

[0040] In one embodiment, the lubricity enhancing component or coatingis derived from a hydrophilic, water soluble precursor component ormaterial including the aforementioned substituent component or groups,an alkylene oxide component and the reactive substituent component orgroups effective to covalently bond with the substrate, that is thepolymeric material of the hollow tube. Such reactive groups, or at leasta portion of such reactive groups, are effective to form homopolymers ofthe precursor material. The alkylene oxide component, for example, inthe form of a polyalkylene glycol component and the like, may beselected from, for example, ethylene oxide components, propylene oxidecomponents, and the like, and mixtures thereof. The alkylene oxidecomponent is preferably an ethylene oxide component, for example apolyethylene glycol component. The reactive substituent component orgroups are preferably selected from ethylenically unsaturated groups,and are more preferably selected from vinyl groups, acrylic groups,methacrylic groups, and the like, and mixtures thereof.

[0041] In an especially useful embodiment, the precursor material of thelubricity enhancing component is a hydrophilic, water solubleacrylic-based monomer such as methoxy polyethylene glycolmonomethacrylate (mPEGMA). Coatings based on mPEGMA are very effective.In one advantageous embodiment, a coating utilizing a mixture of mPEGMAcomponents of differing molecular weights, such as mPEGMA of threedifferent molecular weights, has been found to be highly lubricious andstable. Without wishing to limit the invention to any particular theoryof operation, it is believed that the heaviest, or highest molecularweight, mPEGMA component forms a relatively secure covalent bond withthe polymeric material of the inserter tube, thus improving thestability of the coating, while the lightest, or lowest molecularweight, mPEGMA component is more loosely bound, providing enhancedlubricity.

[0042] One useful method of covalently bonding a lubricity enhancingcomponent, such as mPEGMA or any of the other above-identifiedcompositions, to IOL injection tube 14 is as follows. Non-compoundedpolypropylene resin is used to mold the tube 14 per normal manufacturingpractice. Once the tube 14 is formed, it is exposed to an effectiveplasma for an effective amount of time to activate, or Aprime@, theexposed surfaces thereof so that such exposed surfaces are moresusceptible to being wetted by a solution of the precursor material. Theplasma may have its origin for any of a variety of materials, preferablygases, in particular gases such as oxygen, helium, nitrogen, argon, andthe like and mixtures thereof. More preferably, a plasma containing amixture of oxygen and argon is used.

[0043] In accordance with one embodiment of the present invention, thetube is subjected to plasma processing using a PS-150 plasma unit. Theplasma includes oxygen at a flow rate of 20 cc/min and argon at a flowrate of 10 cc/min. The duration of treatment is about 5 minutes.

[0044] After plasma treatment, the precursor material is applied to thewall, for instance by spraying, brushing, immersion, irrigation, or thelike. The precursor-coated, or wetted, wall is then exposed toconditions effective to cause the precursor material to form a lubricityenhancing component, or coating, having covalent bonds with thepolymeric material of the tube. Then the coated wall is post-cured atconditions effective to enhance the stability of the coating.

[0045] Preferably, the precursor material includes radical initiators,for instance UV and/or thermal radical initiators. The step of causingthe precursor material to form a covalently bonded lubricity enhancingcomponent preferably includes exposing the coating on the interior wallto conditions suitable for activating the initiator or initiators.Advantageously, the precursor material includes both UV and thermalradical initiators, and the step of exposing the coating on the interiorwall to conditions suitable for activating the initiator or initiatorsincludes a first stage of exposing the coating on the wall toultraviolet light to form a covalently bonded coating on the interiorwall, and a second stage of exposing the covalently bonded coating onthe wall to elevated temperatures for a time sufficient to enhance thestability of the covalently bonded coating. Preferably, after thecoating has been exposed to the UV light and/or elevated temperatures,unreacted monomer is removed from the cartridge surface, for instance bywashing.

[0046] Any suitable UV initiator and/or thermal initiator may beemployed provided such materials have no substantial detrimental effecton the inserter, on the IOL to be inserted or on the patient in whoseeye the IOL is inserted. Useful such initiators are well known andcommercially available. In one useful embodiment, the UV initiator inthe precursor material comprises a mixture ofBis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphineoxide, and1-hydroxy-cyclohexyl-phenyl-ketone. This initiator is activated byexposing the precursor material to UV light for about 10 minutes. Auseful thermal initiator in the precursor material comprises2,5-dimethyl-2,5-bis(2-ethyl hexanoyl peroxy)hexane, which is activatedby placing the inserter in an oven for an hour or more at 90° C.However, the specific initiators, exposure times, temperatures and/orother parameters may be varied depending on factors such as theequipment and the particular inserter and inserter components involved,and can readily be optimized based on the disclosure herein usingroutine experimentation.

[0047] A method of using the IOL inserter 10 according to the presentinvention is illustrated in FIGS. 3 to 7. The structure of the inserter10, however, is merely illustrative of the inserters included within thescope of the present invention, and is not intended to be limiting.Inserters including the covalently bonded lubricity enhancing componentsdescribed herein and having configurations substantially different fromIOL inserter 10 are also included within the scope of the presentinvention.

[0048] The body of IOL inserter 10 (that is other than coating 20) is anintegrally formed, for example, molded, unit made of non-compoundedpolypropylene. Load chamber 12 includes a first member 16 and a secondmember 18, hingedly secured to one another and moveable with respect toeach other along line 21, which is parallel to the longitudinal axis 30of the inserter 10.

[0049] Injection tube 14 includes a proximal end portion 22, a distalend portion 24 and an open distal end 26. A reinforcing collar 28 iscoincidental with the proximal end portion 22 of injection tube 14.Injection tube 14 also includes a through slot 32.

[0050] As shown in FIG. 3, inserter 10 is in the opened position. Incontrast, in FIG. 4, inserter 10 is shown in the closed position. In theclosed position, the load chamber 12 includes a top 32 which is acombination of top surfaces 34 and 36 of first wing 38 and second wing40, respectively. First and second wings 38 and 40 are effective for ahuman user of inserter to hold and manipulate the inserter 10 whileusing it, as described hereinafter.

[0051] Inserter 10 is described in more detail with reference to FIG. 5,which shows the inserter in combination with hand piece 70. When used incombination with hand piece 70, the load chamber 12 of inserter 10 is inthe closed position, as shown in FIG. 4.

[0052] Referring to FIG. 6, with load chamber 12 in the closed position,the load chamber includes an interior wall 51 which defines a firstlumen that is elongated in a direction parallel to the longitudinal axis30 of inserter 10. Injection tube 14 includes a tapering interior wall53 which defines a distally tapering second lumen 54.

[0053] The first lumen 52 is aligned with the second lumen 54 so that afolded IOL in the first lumen can be passed directly from the firstlumen into the second lumen. The taper of proximal portion 58 of secondlumen 54 is more severe than the slight taper which exists in the distalportion 60 of the second lumen. The more severe taper in the proximalportion 58 is effective to further fold the IOL as the IOL is passedinto the second lumen. This further folding is advantageous because thefurther folded IOL can be inserted into the eye through a smallerincision. The coating 20 also advantageously reduces the risk of tearingand/or otherwise damaging the IOL as the IOL is passed through the firstlumen 52 and the second lumen 54.

[0054] With reference to FIG. 5, inserter 10 is shown in combinationwith hand piece 70 and push rod member 72. Hand piece 70 includes arelatively large, elongated first through opening 74 and a relativelysmall, elongated second through opening 76. Hand piece 70 also includesa through bore 78 which extends from the proximal end 80 to the distalend 82 of the hand piece. The proximal end portion of hand piece 70includes threads 86 adapted to engage and mate with threads 88 of theproximal segment 90 of push rod member 72. Rod element 92 of push rodmember 72 is adapted to pass through bore 78, first lumen 52, secondlumen 54 and out of open distal end 26. Hand piece 70 and push rodmember 72 are made of metal, such as surgical grade stainless steel orthe like metals. The distal end portion of rod member 72 can be made ofa soft polymeric material, for example, configured to be introduced intoand held in a fold of a folded IOL as the IOL is passed through theinserter.

[0055] Inserter 10 is operated and functions as follows. When it isdesired to load an IOL into inserter 10, the inserter is placed, forexample, manually placed, in a configuration as shown in FIG. 3. Withload chamber 12 in the opened position, a quantity of an ophthalmicallyacceptable liquid is placed in the troughs formed by the first andsecond members 16 and 18 throughout the injection tube. This liquidcomponent is effective, together with the lubricity enhancing component20, in facilitating the passage of the IOL through the inserter 10.Although any suitable liquid component may be employed, particularuseful are liquid aqueous components. Examples include liquid aqueoussalt solutions, such as commercially available balanced salt solutions;and liquid aqueous media including visco elastic components, such ashyaluronate alkali metal salts, hydroxypropylmethyl cellulose, otherwater soluble cellulose derivatives, condroitin sulfate, mixturesthereof, and the like.

[0056] After the liquid component has been provided, an IOL, such asshown generally at 100, is placed, for example, using forceps, inbetween first and second members 16 and 18. This placement is such thatthe anterior face 102 of optic 104 faces upwardly, as shown in FIG. 3.The optic 104 is made of a silicone polymeric material. The filamenthaptics 106 and 108 of IOL 100 are located as shown in FIG. 3, so thatthe fixation members are located generally parallel to, rather thantransverse to, the longitudinal axis 30.

[0057] With IOL 100 placed as shown in FIG. 3, first and second members16 and 18 are hingedly moved relative to each other, for example, bymanually bringing first and second wings 38 and 40 together, to placethe load chamber 12 in the closed position, as shown in FIG. 4. Withload chamber 12 in the closed position, IOL 100 is in a folded state,that is, optic 104 is folded. The relative movement of first and secondmembers 16 and 18 to move the load chamber from the open position to theclosed position is effective to fold the lens. The folded IOL 100 is nowlocated in the first lumen 52. For clarity=s sake, the folded IOL is notshown in any of FIGS. 4, 5, 6 or 7.

[0058] With the inserter 10 configured as shown in FIG. 4 and folded IOL100 located in the first lumen 52, the inserter 10 is placed inassociation with hand piece 70, as shown in FIG. 5. In thisconfiguration, the distal end portion 24 of injection tube 14 extendsdistally beyond the distal end 82 of hand piece 70. As shown in FIG. 6,the distal portion 85 of hand piece 70 includes an inner wall 87 whichis configured to receive reinforcing collar 28 in abutting relation.

[0059] With inserter 10 so placed relative to hand piece 70, push rodmember 72 is pushed in to the through bore 78 and into the inserter 10to push the IOL 100 from the first lumen 52 into the second lumen 54. Asthe threads 88 come into contact with and engage threads 86, the pushrod member 72 is rotated, as shown in FIG. 7, so as to thread the pushrod member onto the proximal end portion 84 of hand piece 70. Bygradually moving the push rod element 92 through bore 78 of hand piece70, the folded IOL 100 is urged to move from first lumen 52 into secondlumen 54, through the open distal end 26 and into the eye.

[0060] Referring now to FIG. 7, the IOL 100 is to be placed in eye 120into an area formerly occupied by the natural lens of the eye. FIG. 7shows the sclera 122 having an incision through which the distal endportion 24 of injection tube 14 is passed. Alternately, the incision canbe made through the cornea. Distal end portion 24 has a sufficientlysmall cross-section to pass into the eye 120 through an incision in thesclera 122. Preferably the distal end portion is small enough incross-section to pass through an incision as small as 2.8 mm or less.

[0061] The injection tube 14 is manipulated within eye 122 until it ispositioned so that IOL can be properly positioned in eye, that is, inthe anterior chamber, posterior chamber, capsular bag 124, or sulcus,after being released. Thus, the surgeon is able to controllably positionthe distal end portion 24 of injection tube 14, with IOL 100 in thefirst lumen 52 of load chamber 12. Once distal end portion 24 is sopositioned, the rod element 92 is urged distally, by rotating(threading) push rod member 72 onto hand piece 70, to pass the IOL 100into and through the second lumen 54, through the open distal end 26 ofinjection tube 14 and into the eye 120. The anterior face 102 of IOL 100faces generally forwardly in the eye 120 as the IOL is released from theinserter 10. In other words, the IOL 100 passes through the first lumen52, second lumen 54 and open distal end 26 and into eye 120 withoutflipping or otherwise becoming misplaced. Only a relatively small amountof, if any, post-insertion re-positioning is needed to properly positionIOL 100 in the eye 120.

[0062] After the IOL 100 has been inserted into the eye, the rod element92 is moved proximally into the injection tube 14 and the distal endportion of the injection tube is removed from the eye. If needed, theIOL 100 can be repositioned in the eye by a small, bent needle orsimilar tool inserted in the same incision.

[0063] Once the IOL 100 is properly positioned in eye 120 and inserter10 is withdrawn from the eye, the incision in the sclera may be mended,for example, using conventional techniques. After use, inserter 10 ispreferably disposed of. Hand piece 70 and push rod member 72 can bereused, after sterilization/ disinfection.

[0064] The following non-limiting example illustrates certain aspects ofthe present invention.

EXAMPLE

[0065] A precursor material is formed by mixing the following monomersin a suitable container. INGREDIENT % BY WEIGHT mPEGMA mw 1100 6.4%mPEGMA mw 526 9.5% mPEGMA mw 360 2.4% thermal initiator 0.5%(2,5-dimethyl-2,5-bis(2- ethyl hexanoyl peroxy)hexane) photoinitiator1.2% (mixture of Bis(2,6- dimethoxybenzoyl)-2,4,4- trimethyl-pentylphosphineoxide and 1-hydroxy-cyclohexyl- phenyl-ketone) Acetone 80%

[0066] The mixture is applied, using a microbrush, to the interior wallof a non-compounded polypropylene inserter cartridge which has beenpretreated for 5 minutes with a plasma including 20 cc/min oxygen and 10cc/min argon, using a PS-150 plasma unit. The wetted interior wall isthen exposed to UV light for 10 minutes and post-cured in an oven forone hour or more at 90° C. After post-curing, any unreacted monomer isremoved, for instance by washing the cartridge.

[0067] A series of tests is run to evaluate the lubricity of the abovemPEGma-coated inserter cartridge (Cartridge A) in comparison to acontrol cartridge of the type sold by Advanced Medical Optics, Inc.(Santa Ana, Calif.) under the trademark Unfolder Sapphire SeriesImplantation System (Cartridge B), and to cartridges, identified belowas Cartridges C, D, and E, coated with hydroxypropylmethyl cellulose(HPMC), poly 1-vinyl-2-pyrrolidinone (PVP), and polyethyleneglycolacrylate (PEGA), respectively. All the cartridges are identical to oneanother in structure.

[0068] The control cartridge, of the type described in theaforementioned Makker U.S. Pat. No. 5,716,364, is molded frompolypropylene including 0.25% by weight of glycerol monostearate (GMS),and subjected to plasma processing and blooming processing, causing theGMS to be concentrated at or near, but not covalently bonded to, aninterior wall of the cartridge.

[0069] Cartridges C, D, and E are formed from the same non-compoundedpolypropylene resin as cartridge A, and are subjected to the samepre-treating, curing and post-curing procedures as Cartridge A so thatthe coatings are covalently bonded to the cartridges.

[0070] A series of tests were run to evaluate the lubricity of variousIOL inserters. The lenses used in the testing included optics made ofacrylic based polymeric material. Specifically, the IOLs were those soldby Advanced Medical Optics, Inc. under the trademark Sensar® AR40e,brand of IOL (Santa Ana, Calif.).

[0071] The test procedure used is as follows. The IOL is loaded into theloading chamber and the inserter is placed into the hand piece. Anamount of commercially available aqueous solution approximately equal tothe volume of the IOL optic is dispensed into the loading chamber. Incertain tests, the IOL is immediately advanced through the loadingchamber and forward tube and then out the distal port. In other tests,the IOL is allowed to dwell in the loading chamber (Stage 1) for threeminutes, advanced into the forward tube and then immediately released.In still other tests, the IOL is immediately advanced through theloading chamber, and then allowed to dwell in the forward tube (Stage 2)for three minutes before being released out the distal port.

[0072] The amount of torque required to advance the IOL through theinserter cartridge under the various dwell time scenarios is measured,and the results averaged for each inserter. The results are as follows:INSERTER AVERAGE TORQUE (gm-cm) A 327 B 733 C 1117  D 792 E 871

[0073] These results indicate that Inserter A, which includes acovalently bonded mPEGMA coating in accordance with the presentinvention, requires lower torque to advance an IOL through the cartridgethan is required by each of the other inserters, including the controlinserter B, which includes a non-covalently bonded GMS lubricityenhancing component concentrated near its interior wall. Thus, acovalently bonded mPEGMA coating according to the present invention isdemonstrated to be more lubricious than the prior art non-covalentlybonded GMS lubricity enhancing component.

[0074] In addition, the present coatings, for example derived frommPEGMA of different molecular weights are more stable, e.g. allow theinserter to have a longer effective shelf life, relative to other coatedinserters, whether the lubricity enhancing component is covalentlybonded or not. The use of methoxy polyethylene glycol monomethacrylate(mPEGMA) is effective to reduce hydrolysis of the resulting coatingrelative to other coatings, such as polyethylene glycol monomethacrylatewith no methoxy groups, and provides for a more stable coating.

[0075] While this invention has been described with respect to variousspecific examples and embodiments, it is to be understood that theinvention is not limited thereto and that it can be variously practicedwithin the scope of the following claims.

What is claimed is:
 1. A novel enhanced tubular means for inserting anintraocular lens through a small incision into an eye, comprising, incombination: a hollow tube means including an interior wall defining ahollow space through which an intraocular lens may be passed from thehollow space into an eye; and a lubricity enhancing component covalentlybonded to the hollow tube at the interior wall in an amount effective tofacilitate the passage of the intraocular lens through the hollow space,the lubricity enhancing component including at least one improvedsubstituent component for reducing hydrolysis of said lubricityenhancing component relative to an identical lubricity enhancingcomponent without the at least one improved substituent component. 2.The means of claim 1 wherein said substituent component is other thanhydroxy.
 3. The means of claim 1 wherein the substituent component isselected from the class consisting of hydrocarbyl groups, substitutedhydrocarbyl groups and mixtures thereof.
 4. The means of claim 3 whereinthe substituent component has 1 to about 4 carbon atoms per group. 5.The means of claim 1 wherein the substituent component is selected fromthe class consisting of alkoxy groups having 1 to about 4 carbon atomsand mixtures thereof.
 6. The means of claim 1 wherein the substituentcomponent includes one or more methoxy groups.
 7. The means of claim 1wherein the substituent component is effective to reduce hydrolysis ofsaid lubricity enhancing component relative to an identical lubricityenhancing component including one or more hydroxy groups in place of thesubstituent component.
 8. The means of claim 1 wherein said lubricityenhancing component is hydrophilic.
 9. The means of claim 1 wherein saidlubricity enhancing component is derived from a precursor componentincluding the substituent component, an alkylene oxide component and anadditional substituent component effective to covalently bond with atleast one of the precursor component and the hollow tube.
 10. The meansof claim 9 wherein said additional substituent component is anethylenically unsaturated group.
 11. The means of claim 9 wherein saidalkylene oxide component is an ethylene oxide component.
 12. The meansof claim 9 wherein the additional substituent component is selected fromthe class consisting of vinyl groups, acrylic groups, methacrylic groupsand mixtures thereof.
 13. The means of claim 9 wherein the precursorcomponent is water soluble.
 14. The means of claim 9 wherein theprecursor component is methoxy polyethylene glycol monomethacrylate. 15.The means of claim 1 wherein the lubricity enhancing component iseffective to reduce the force needed to pass the intraocular lensthrough the hollow space relative to the force needed to pass anidentical intraocular lens through the hollow space of a similarapparatus without the lubricity enhancing component.
 16. The means ofclaim 1 which further comprises a loading portion coupled to the hollowtube and sized and adapted to receive an intraocular lens for passageinto the hollow space.
 17. The means of claim 16 wherein the lubricityenhancing component is covalently bonded to said loading portion in anamount effective to at least assist in facilitating the passage of saidintraocular lens into said hollow space.
 18. A method of making anintraocular lens inserter cartridge, comprising: providing a hollow tubecomprising a polymeric material, the tube including an interior walldefining a hollow space through which an intraocular lens may be passedand an outlet through which the intraocular lens may be passed from thehollow space into an eye; contacting the interior wall of the tube witha precursor material of a lubricity enhancing component to form acoating on the interior wall; and causing the precursor material in thecoating to form a lubricity enhancing component having covalent bondswith the polymeric material of the tube; wherein the lubricity enhancingcomponent includes at least one substituent group effective to reducehydrolysis of the lubricity enhancing component relative to an identicallubricity enhancing component without the at least one substituentgroup.
 19. The method of claim 18, further comprising a step of exposingthe interior wall to plasma for a sufficient amount of time to enhancethe covalent bonding between the lubricity enhancing component and thepolymeric material of the tube.
 20. The method of claim 18, wherein thepolymeric material comprises polypropylene.
 21. The method of claim 18,wherein the precursor material includes a UV radical initiator, and thestep of causing comprises exposing the coating on the interior wall toultraviolet light to covalently bond the coating on the interior surfaceof the tube.
 22. The method of claim 21, wherein the precursor materialfurther includes a thermal radical initiator, and the step of causingfurther comprises exposing the covalently bonded coating to elevatedtemperature for a time sufficient to enhance the stability of thecovalently bonded coating.
 23. The method of claim 18, wherein thelubricity enhancing component is effective to reduce the force needed topass the intraocular lens in a folded state through the hollow spacerelative to the force needed to pass an identical intraocular lens in afolded state through the hollow space of an identical hollow tubewithout the lubricity enhancing agent.
 24. The method of claim 18wherein the at least one substituent group is other than a hydroxygroup.
 25. The method of claim 24 wherein the at least one substituentgroup is selected from the class consisting of hydrocarbyl groups,substituted hydrocarbyl groups and mixtures thereof.
 26. The method ofclaim 25 wherein the at least one substituent group has 1 to about 4carbon atoms per group.
 27. The method of claim 24 wherein the at leastone substituent group is selected from the class consisting of alkoxygroups having 1 to about 4 carbon atoms and mixtures thereof.
 28. Themethod of claim 24 wherein the at least one substituent group is one ormore methoxy groups.
 29. The method of claim 24 wherein the substituentgroup is effective to reduce hydrolysis of said lubricity enhancingcomponent relative to an identical lubricity enhancing componentincluding one or more hydroxy groups in place of the at least onesubstituent group.
 30. The method of claim 24 wherein said lubricityenhancing component is hydrophilic.
 31. A method for inserting anintraocular lens into an eye comprising: placing an outlet of a hollowtube in or in proximity to an incision in an eye, the hollow tubeincluding an interior wall defining a hollow tube including an interiorwall defining a hollow space containing an intraocular lens in a foldedstate and an effective amount of a liquid component, and an effectiveamount of a lubricity enhancing component covalently bonded to thehollow tube at the interior wall, the lubricity enhancing componentincluding a substituent component effective to reduce hydrolysis of thelubricity enhancing component relative to an identical lubricityenhancing component without the substituent component; and passing theintraocular lens from the hollow space through the outlet into the eye.